Liquid-bearing data recording disk file with transducer carrier having rear ski pad at the head-disk interface

ABSTRACT

A data recording disk file of the liquid-bearing type has an improved head-disk interface provided in by a transducer carrier (100) with new properties. The carrier (100) supports a conventional head (109) for reading and writing data to the disk (130). The carrier has an air-bearing surface (110,112) near its front end, a ski pad (118) near its rear end, and a plurality of ski feet or struts (120,122) which support the air-bearing surface off the liquid film (146) of the disk when the disk file is not operating. The air-bearing surface is in the form of a pair of air-bearing rails (110,112) located outboard of the rear ski pad so that no air-bearing effect occurs in the rearward region of the carrier to assure the skiing action of the rear ski pad. As operational speed is approached the air-bearing lifts the struts off the disk and the rear ski pad is the sole ski foot on the liquid film. The rear ski pad has a convexly shaped leading edge which is wider than its trailing edge to minimize static friction and lubricant thinning during skiing, and the angle between the leading and trailing edges of the pad is selected to enable the pad to ski over the wide ranges of carrier-disk velocity which occur as the carrier moves from disk ID to OD. &lt;IMAGE&gt;

TECHNICAL FIELD

This application is related to concurrently-filed co-pending applicationU.S. Ser. No. 07/876,843.

This invention relates to data recording disk files of the type referredto as liquid-bearing disk files wherein the head or transducer carrierand a liquid lubricant on the disk surface provide a new type ofhead-disk interface. More particularly, the invention relates to aliquid-bearing disk file having an improved transducer carrier at thehead-disk interface.

BACKGROUND OF THE INVENTION

Disk files, also referred to as disk drives, are information storagedevices which utilize a rotatable disk with concentric data trackscontaining the information, a head or transducer for reading or writingdata onto the various tracks, and an actuator connected to a carrier forthe head for moving the head to the desired track and maintaining itover the track centerline during read or write operations. There aretypically a plurality of disks separated by spacer rings and stacked ona hub which is rotated by a disk drive motor. A housing supports thedrive motor and head actuator and surrounds the head and disk to providea substantially sealed environment for the head-disk interface. Inconventional magnetic recording disk files the head carrier is anair-bearing slider which rides on a bearing of air above the disksurface. The slider is maintained against the disk surface by a smallforce from a suspension which connects the slider to the actuator, sothat the slider is in contact with the disk surface during start andstop operations when there is insufficient disk rotational speed tomaintain the air-bearing. A lubricant is required on the disk surface toprevent damage to the head and disk during starting and stopping of thedisk file.

There are several references which describe different types of headcarriers and liquid-bearings as possible alternatives to theconventional air-bearing head-disk interface in magnetic recording diskfiles. In assignee's U.S. Pat. No. 2,969,435, a sled-type transducercarrier with a large flat surface rides on a layer of oil on the disk,the oil being supplied from an oil reservoir external to the disk fileand discharged from a nozzle located ahead of the carrier. In assignee'spending application, U.S. Ser. No. 264,604, filed Oct. 31, 1988, andpublished May 9, 1990 as European published application EP 367510, adisk file utilizes a continuously recirculating low viscosity liquidlubricant, which is maintained as a relatively thick layer on the disk,and a transducer carrier which has triangular shaped feet to plowthrough the low viscosity liquid layer. The EP reference suggests thatif the disk file is hermetically sealed with no air present the lowvapor pressure lubricant can evaporate which allows the requiredrecirculation of the lubricant to occur by distillation.

More recently, in assignee's co-pending applications U.S. Ser. Nos.07/724,646 and 07/724,696, a liquid-bearing disk file and transducercarrier have been described wherein a non-recirculating high viscositylubricant film is maintained on the disk and a transducer carrier,having specially adapted ski feet, skis on the liquid film as the diskrotates. The transducer carrier described in those applications is amodified three-rail air-bearing slider which has a forward ski footformed on each of the outer rails and a rear ski foot formed on thecenter rail, the ends of the three ski feet being essentially coplanar.When the disk file reaches operating speed, the forward ski feet areraised above the liquid film due to the air-bearing effect of the sliderrails, while the liquid lubricated rear ski foot skis on the liquidfilm.

There are several challenges facing the developers of improvedliquid-bearing disk files with skiing transducer carriers. The carriermust provide a low static friction ("stiction") head-disk interfacebecause liquid-bearing disk files generally have larger amounts of freelubricant and smoother disks than air-bearing disk files. The carriermust also be designed to minimize lubricant depletion from the disk. Inaddition, the carrier must be able to perform adequately over a widerange of relative carrier-disk velocities which occur at different diskradii. Thus, what is needed is a liquid-bearing disk file with animproved head-disk interface which reduces stiction, minimizes lubricantdepletion from the disk, and permits the transducer carrier to ski overa wide range of velocities.

SUMMARY OF THE INVENTION

The invention is a liquid-bearing disk file having an improved head-diskinterface provided in part by a transducer carrier with new properties.The carrier has an air-bearing surface near its front end, a ski padnear its rear end, and a plurality of ski feet or struts which supportthe air-bearing surface off the liquid film of the disk to provide astatic pitch-up for the carrier when the disk file is not operating. Theair-bearing surface is in the form of a pair of air-bearing railslocated outboard of the rear ski pad so that only a minimal air-bearingeffect occurs in the rearward region of the carrier to assure the skiingaction of the rear ski pad. As operational speed is approached theair-bearing lifts the struts off the disk and the rear ski pad is thesole ski foot on the liquid film. The skiing function of the rear skipad is facilitated by the shallow angle between the rear ski pad and theliquid film on the disk due to the static pitch-up position of thecarrier. The rear ski pad has a convexly shaped leading edge which iswider than its trailing edge to minimize stiction and lubricant thinningduring skiing, and the angle between the leading and trailing edges ofthe pad is selected to enable the pad to ski over the wide ranges ofcarrier-disk velocity (and corresponding skew angle between the carrierand a tangent to the disk track in rotary actuator disk files) whichoccur as the carrier moves from disk ID to OD.

For a fuller understanding of the nature and advantages of the presentinvention, reference should be made to the following detaileddescription taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view in section of a schematic of a liquid-bearing diskfile;

FIG. 2 is an open top view of the disk file depicted schematically inFIG. 1;

FIG. 3 is a perspective view of a spacer ring lubricant reservoir shownin partial cutaway of the type used in a liquid-bearing disk file;

FIG. 4 is a plan view of the bottom or disk side of an air-bearingslider modified to have a ski surface;

FIG. 5 is a sectional view of the carrier-disk interface of aliquid-bearing disk file with a skiing transducer carrier;

FIG. 6 is a plan view of the disk side of the skiing transducer carrierof the present invention;

FIG. 7 is a side view of the carrier of FIG. 6 on a disk;

FIGS. 8A and 8B are plan views of alternative embodiments of the skiingtransducer carrier of the present invention, illustrating alternativepositions of the front ski feet or struts;

FIGS. 8C and 8D are alternative embodiments of the skiing transducercarrier of the present invention, illustrating additional ski feet orstruts for supporting the carrier when the disk file is not operating;and

FIGS. 9A-9F are sectional views of the skiing transducer carrier of FIG.8A illustrating sequential steps in the fabrication of the carrier ofFIG. 8A.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Liquid-Bearing Disk File WithSkiing Carrier

The liquid-bearing disk file with the skiing transducer carrierreferenced in the co-pending applications will be described briefly withrespect to FIGS. 1-5.

Referring first to FIG. 1, there is illustrated in sectional view aschematic of a liquid-bearing disk file. The disk file comprises a base10 to which are secured a disk drive motor 12 and an actuator 14, and acover 11. The base 10 and cover 11 provide a substantially sealedhousing for the disk file. Typically there is a gasket 13 locatedbetween base 10 and cover 11 and a small breather port (not shown) forequalizing pressure between the interior of the disk file and theoutside environment. This type of disk file is described as beingsubstantially sealed since the drive motor 12 is located entirely withinthe housing and there is no external forced air supply for cooling theinterior components. A magnetic recording disk 16 is connected to drivemotor 12 by means of hub 18 to which it is attached for rotation by thedrive motor 12. A read/write head or transducer (not shown) is formed ona transducer carrier 20. The carrier 20 is connected to the actuator 14by means of a rigid arm 22 and a suspension 24, the suspension 24providing a biasing force which urges the transducer carrier 20 onto thesurface of the recording disk 16. During operation of the disk file thedrive motor 12 rotates the disk 16 at a constant speed, and the actuator14, which is typically a linear or rotary voice coil motor (VCM), movesthe transducer carrier 20 generally radially across the surface of thedisk 16 so that the read/write head may access different data tracks ondisk 16.

FIG. 2 is a top view of the interior of the disk file with the cover 11removed and illustrates an annular lubricant reservoir 30, which servesas a means for holding a supply of liquid lubricant for replenishment ofthe liquid film on the surface of disk 16. A thin continuous film of arelatively high viscosity lubricant is maintained on the surface of disk16 and is replenished by lubricant from the reservoir 30 duringoperation. FIG. 2 also illustrates in better detail the suspension 24which provides a force to the carrier 20 to maintain the carrier incontact with the lubricant film on the disk 16. The suspension may be aconventional type of suspension such as that used in magnetic disk fileswhich have an air-bearing slider. An example is the well-known Watroussuspension, as described in assignee's U.S. Pat. No. 4,167,765, which isincorporated herein by reference. This type of suspension also providesa gimballed attachment of the transducer carrier which allows thecarrier to pitch and roll as it rides on the liquid lubricant film.

The annular lubricant reservoir 30, which may also serve as a diskspacer in disk files which have multiple disks in a disk stack, is shownin detail in FIG. 3. The reservoir 30 comprises a ring or annulus 32which is machined from a porous, sintered metal, such as sinteredstainless steel. Thereafter the outer surface of the annulus 32 isentirely sealed, either by electroplating a material such as gold or byelectroless plating of a nickel film, to provide a film 34 surroundingthe sintered stainless steel. Openings 36 are then formed in the gold ornickel surface film 34 to unseal the reservoir and provide a means forthe lubricant stored inside to escape. This is accomplished by machiningseveral, e.g typically 4, small areas on the surface film 34 by etching,ablation or electrostatic discharge machining, which creates theopenings 36 or pores in those areas. The reservoir is then filled withlubricant by placing it in a vacuum, immersing it in the lubricant, andheating it slightly to increase the rate at which it fills. The numberand size of the openings 36 are selected to provide the desired amountof controlled lubricant escape during operation of the disk file, whichis designed to match the rate at which lubricant leaves the disk. Whenthe annulus 32 is designed to also serve as a spacer ring in disk fileswhich have multiple disks supported in a stack on the hub 18, theopenings 36 may be located nearer to the portions of the spacer ringwhich are in contact with the disks, so that selected openings areassociated with one of the corresponding disk surfaces. In addition tothe size of the openings 36, the factors which affect the rate oflubricant leaving the disk include the smoothness of the disk, the diskrotational speed, the viscosity of the lubricant, and the carrierdesign. When the disk is not rotating, the capillary action of theporous sponge-like material of annulus 32 holds the liquid inside thereservoir.

While the specific type of lubricant reservoir or holding means is notpart of the present invention, there are numerous alternative reservoirswhich are possible. For example, in some applications where the totalrunning time of the disk file is relatively short (e.g. several months),the means for holding the lubricant may be a non-data band or region onthe disk near the inside diameter of the disk. During the normal disklubrication process, the non-data band of the disk is also lubed, sothat the non-data band contains an additional supply of lubricant forreplenishment of the liquid film. In this embodiment for this specificapplication, it may also be desirable to use a lubricant which has ahigher viscosity so that the rate of depletion is somewhat reduced.

FIG. 4 illustrates the transducer carrier, denoted 20, which isdescribed in assignee's co-pending application U.S. Ser. No. 07/724,696.The ski feet 40, 42, 44 are formed on a conventional three-railair-bearing slider, such as that described in assignees' U.S. Pat. No.4,894,740. Each of the ski feet 40, 42, 44 is formed on the conventionalbottom surface of the rails 50, 51, 52 by material etching the railsback a few thousand Angstroms, preferably by ion milling oralternatively by reactive ion etching or other etching means. The resultis that the ski feet are the remaining outer portions of the railsprojecting outwardly from the newly defined rails of the slider, withthe ends of the ski feet being essentially coplanar. The ion milling isperformed in a manner such that there is a slight taper of the ski feetaway from the outer surface of the rails. This taper of the ski feetallows the transducer carrier to actually ski on top of the relativelyhigh viscosity lubricant film on the disk.

The interface between the transducer carrier and the disk with thelubricant film is illustrated in FIG. 5. In the preferred embodiment,the disk 16 has as its upper solid portion a conventional amorphouscarbon overcoat film 60, which is typically approximately 250 Angstromsthick. The magnetic layer 62, such as a conventional cobalt alloysputter deposited magnetic film, is located beneath the protectivecarbon overcoat 60. The liquid lubricant is deposited as a film 64,preferably to a thickness in the range of approximately 20 to 100Angstroms, on top of the carbon overcoat 60. A portion of one of the skifeet 40 is depicted as being supported on the lubricant film 64. The endof ski foot 40 has a diameter of approximately 100 microns and istapered at approximately a ten degree angle to an etch depth ofapproximately 4,000 Angstroms. The transducer 46 (FIG. 4) is supportedon the trailing edge of the carrier 20 at the end of ski foot 44, and sois maintained at a spacing of approximately the lubricant film thickness(e.g. 20 to 100 Angstroms) from the top of the recording disk. Duringoperation of the disk file the suspension 24 (FIG. 2) maintains a forceon the carrier 20 forcing the ski feet 40, 42, 44 into contact with thelubricant film 64, which, because it is essentially incompressible,serves as a spacing layer between the carrier 20 and the disk 16. Therelatively small angle between the end of ski foot 40 and the disk (10degrees in FIG. 5) improves the ability of the carrier to ski as itprovides less of a barrier to the lubricant which passes under the endof ski foot 40 during start up of the disk file. When the disk filereaches operating speed, the air-bearing rails 50, 51 cause the ski feet40, 42 to lift off the liquid film, while the suspension maintains skifoot 44 in skiing contact with the liquid film.

Liquid-Bearing Disk File With Skiing Carrier of Present Invention

Referring now to FIGS. 6 and 7, there is illustrated an improved skiingtransducer carrier 100. Carrier 100 has a disk side 102, a back side104, a front end 106 and a trailing end 108. A transducer 109, such as aconventional thin film head for reading or writing data from the disk,is formed on the trailing end 108 of carrier 100. Head 109 may be aninductive read and write transducer or an inductive write transducerwith a magnetoresistive (MR) read transducer formed by thin filmdeposition techniques as is well known in the art. An air-bearingsurface is provided on the disk side 102 of carrier 100 in the form of apair of rails 110, 112, each rail having a respective front taper 114,116. Also located on the disk side 102 near trailing end 108 is a skifoot or pad 118 which provides a skiing surface for skiing on the liquidfilm 146 maintained on disk 150 (FIG. 7). As shown in FIG. 7, the skiingsurface of ski pad 118 is essentially coplanar with the air-bearingsurface of rails 110, 112. Extending from the air-bearing rails 110, 112near the rear end of tapers 114, 116 are a pair of forward ski feet orstruts 120, 122. As depicted in FIG. 7, the struts 120, 122 provide astatic pitch-up position for carrier 100 when the carrier is at rest onthe surface of disk 150. Thus, when at rest the air-bearing surface ofrails 110, 112 is maintained essentially out of contact with the liquidfilm 146 on disk 150, thereby minimizing the static friction at thecarrier-disk interface. The static pitch-up of the carrier due to thestruts 120, 122 also defines the shallow angle between ski pad 118 andthe liquid film 146 on the disk, which facilitates the skiing functionof the ski pad, in the manner as described with respect to FIG. 5. Inaddition, the ends of the struts, because they are in a plane parallelto but not coplanar with the ski pad surface, also define a shallowangle with the liquid film. The dimensions of air-bearing rails 110, 112are selected such that at the low end of the velocity range of operationof the disk file approximately 80% of the suspension load is borne bythe air-bearing, while the remaining load is borne by ski pad 118. Thus,at operational speed the front end of carrier 100 and the struts 120,122 are maintained out of contact with the liquid film 146 and the rearski pad 118 skis on the liquid film 146, in the manner essentially asshown in FIG. 7. Because there is lack of any significant air lift inthe rear region of the carrier 100 due to the absence of air-bearingrails in that region, the ski pad 118 is maintained in contact with theliquid film 146 on the disk 150 over a wide velocity range. Thismaintains the transducer 109 in close spacing to the magnetic layer onthe disk 150.

Ski pad 118 has a leading edge 124 which is wider than its trailing edge130. The sides 126, 128 of ski pad 118 are thus slanted relative to thelength of the slider. In the preferred embodiment the sides 126, 128 areangled approximately 20 degrees relative to the length of the slider. Bymaking the rear ski pad 118 wider in the front than in the back, the skipad 118 is prevented from acting as a plow, thereby minimizing depletionof the lube in the wake of movement of the disk 150 under the ski pad118. This also maintains low drag and results in a minimization ofthinning of the lubricant under the pad 118. In disk files with rotaryactuators, the length of the slider is tangent to the disk at only onetrack position. For example, in one commercially available 2 1/2" diskdrive the slider is skewed at approximately -4 degrees at the insidediameter (ID) and +17 degrees at the outside diameter (OD). By makingthe angle of the sides 126, 128 of ski pad 118 greater than the maximumabsolute value of skew, for example approximately 20 degrees, it isassured that the ski pad remains non-plowing over the complete anglerange of operation of the disk file as the carrier moves from disk ID todisk OD. This permits the carrier 110 to ski properly over the fullrange of relative carrier-disk velocities experienced from disk ID toOD.

The leading edge 124 of ski pad 118 has an essentially convex curvaturewith a radius of curvature on the order of the width of thestraight-back trailing edge 130. The local convexity of the shape ofleading edge 124, combined with the fact that the front portion ofcarrier 100 is maintained off of the surface of disk 150 as shown inFIG. 7, minimizes any plowing action and guides any loose debris thatmay be present on the disk to either side of pad 118.

It has been determined that with the rear ski pad design of the presentinvention it is possible to eliminate the lubricant reservoir for somedisk file applications. In one experiment several liquid bearing diskfiles were assembled without a lubricant reservoir of any type and witha transducer carrier like that depicted in FIG. 4, but modified so thatthe rear ski pad 44 had the shape of the ski pad 118 in FIG. 6. Thesefiles have operated continuously for over five months, with onlyoccasional start/stops and intermittent tear downs to check for wear. Nowear has been observed and the files continue to operate. Thus whilethere are some applications of disk files which will require very longrun times and thus some means of maintaining the liquid film on the diskwill be a necessity, in certain applications where the run time issignificantly shorter, the transducer carrier of the present inventionwill permit the elimination of a reservoir. Such disk files will thus beless complex and costly.

Referring now to FIGS. 8A-8B, there are illustrated other embodiments ofthe carrier wherein the struts 120, 122 are located inboard or outboardof the air-bearing surface rails 110, 112, rather than on the rails asin the embodiment of FIG. 6. In these embodiments, the struts 120, 122extend directly from the disk side 102 of the carrier. These embodimentshave the advantage that since the struts 120, 122 are not formed on therails 110, 112, any effect on the performance of the air-bearing iseliminated. In addition, at start and stop of the disk file there is noaccumulation of lubricant on the rails near the struts, so that stictionis reduced.

Referring now to FIGS. 8C-8D, there are illustrated alternativeembodiments to the carriers of FIG. 6 and FIGS. 8A-8B in that thecarriers are provided with either 3 or 4 struts to maintain the ski pad118 out of contact with the lubricant film on the disk when the diskfile is not operating. In FIGS. 8C-8D struts 132, 134 are formed on diskside 102 rearward of the center of mass of the carrier. When the carrieris at rest in the disk file, the carrier sits on struts 132, 134 as wellas single forward strut 136 in FIG. 8C or dual forward struts 138, 140in FIG. 8D. At start up of the disk file the transducer carrierinitially skis on all three or four struts and then rotates about therear struts 132, 134 due to the air-bearing lift provided by rails 110,112. At full operational speed the carrier has rotated onto the ski pad118 and all of the struts are maintained out of contact with the liquidfilm on the disk. The advantage of the embodiment of FIG. 8D over thatof FIG. 8C is that because there is no strut directly in the pathbetween the carrier front end 106 and ski pad 118 in the carrier of FIG.8D, lubricant accumulation on the rear ski pad 118 due to spraying atstart and stop is eliminated.

Method of Manufacturing the Skiing Carrier of the Present Invention

The preferred method of manufacturing the skiing transducer carrier willbe described with reference to FIGS. 9A-9F, which illustrate the stepsof manufacturing the carrier depicted in FIG. 8A. FIGS. 9A-9F aresectional views of the carrier taken through a section intersecting thestruts 120, 122.

In FIG. 9A a multilayer overcoat 172 is sputter deposited onto carrierbody 170. The body 170 of the carrier is typically formed of aconventional ceramic mixture of titanium carbide (TiC) and alumina (Al₂O₃). The overcoat 172 comprises a first 50 Angstroms layer of silicon(Si) sputter deposited onto body 170, followed by 150 Angstroms ofamorphous hydrogenated carbon (H:C), 50 Angstroms of Si and a finallayer of 2000 Angstroms H:C. The overcoat, the major portion of which isthe final 2000 Angstroms layer of H:C, is essentially carbon which willultimately form the struts 120, 122. A layer of photoresist, such asRiston brand of poly methylmethacralate (PMMA), is then rolled on top ofovercoat 172 to a thickness of approximately 0.08 millimeters. Thephotoresist is then exposed through a suitable mask which defines apattern corresponding to the air-bearing rails 110, 112, rear ski pad118 and struts 120, 122. After development and removal of the unexposedphotoresist, the carrier is as depicted in FIG. 9B, with photoresistareas remaining over the overcoat 172 in the areas where the air-bearingrails 110, 112, rear ski pad 118 and struts 120, 122 will ultimately beformed. The photoresist areas over the areas where struts 120, 122 willbe formed are identified as photoresist islands 174, 176 in FIG. 9B. Anoxygen plasma etching or ashing process is then performed to remove theSi-C multilayer overcoat in the regions unprotected by photoresist.Thereafter a reactive ion etching process is performed to etch away thecarrier body 170 down to the depth of disk side 102 to define theair-bearing rails 110, 112 and rear ski pad 118, with the result beingdepicted in FIG. 9C. The remaining photoresist is next removed and asecond photoresist layer is applied and exposed and developed, leaving aresist island 178 just over struts 120, 122, as depicted in FIG. 9D. Asubsequent ashing process removes the remaining Si-C multilayer overcoatfrom the areas unprotected by the photoresist, as depicted in FIG. 9E,to define rails 110, 112. Finally, as shown in FIG. 9F, the remainingphotoresist layer 178 is removed, resulting in the completed carrierformed from carrier body 170 and having air-bearing rails 110, 112, andstruts 120, 122 formed of the Si-C multilayer overcoat and extendingbeyond rails 110,112 by approximately 2150 Angstroms, the thickness ofthe sputter deposited Si-C overcoat. While not shown in the sectionalviews of FIGS. 9E and 9F, rear ski pad 118 has also been formed duringthe process with its skiing surface being formed coplanar with theair-bearing surface of rails 110, 112.

Experimental Results

The transducer carrier depicted in FIG. 8A was fabricated by thedescribed process with carbon struts 120, 122 extending from disk side102 to approximately 1400 Angstroms beyond the air-bearing surface ofrails 110, 112. The carrier was tested on a 2 1/2" thin film disk havinga cobalt-platinum-chromium magnetic layer and a 150 Angstroms protectivecarbon overcoat. A conventional perfluoropolyether lubricant (Demnumbrand SP) was applied by dipping to form a liquid film with a thicknessof approximately 40 Angstroms on the carbon overcoat. The load appliedto the carrier by the suspension was in the range of 4-6 grams. Thevelocity at which the struts 120, 122 lifted off the disk was in therange of approximately 3-4 meters per second. The rear ski pad 118 wasmeasured to be in contact with the liquid film from this range up toapproximately 15-20 meters per second. The static friction was measuredto be approximately 5 grams, and the drag was measured to beapproximately 0.1-0.4 grams throughout the file operational velocityrange of 5.5-11 meters per second. Both of these values are adequate toprevent operational problems in the disk file. The thickness of thelubricant was measured as a function of run time during track followingoperation of the disk file. Starting with an initial lubricant thicknessof approximately 40 A, lubricant depletion was measured to be less than5 Angstroms after two days of track following.

While the preferred embodiments of the present invention have beenillustrated in detail, it should be apparent that modifications andimprovements may be made to the invention without departing from thespirit and scope of the invention as described in the following claims.

What is claimed is:
 1. A data recording disk file comprising:at leastone data disk having a liquid film thereon; a motor connected to thedisk for rotating the disk; a transducer for writing data to or readingdata from the disk; a transducer carrier having a disk side, a front endand a trailing end, said transducer being located near said trailingends, the carrier comprising an air-bearing surface on the disk sidenear the front end, a liquid-bearing ski surface on the disk side nearthe trailing end and shaped to have its leading edge wider than itstrailing edge, and a plurality of struts to support the air-bearingsurface away from the disk when the disk is not rotating; an actuatorfor moving the carrier generally radially across the disk so thetransducer may access different regions of data on the disk; meansconnecting the carrier to the actuator for urging the ski surface of thecarrier into contact with the liquid film on the disk during rotation ofthe disk; and means for supporting the motor and actuator.
 2. The datarecording disk file according to claim 1 further comprising means forsupplying liquid to the disk to maintain the liquid film on the disk. 3.A transducer assembly for a data recording disk file which utilizes aliquid-bearing head-disk interface, the assembly comprising:a transducercarrier having a disk side, a front end and a trailing end, the carriercomprising an air-bearing surface on the disk side near the front end, aliquid-bearing ski surface on the disk side near the trailing end andshaped to have its leading edge wider than its trailing edge, and aplurality of struts to support the air-bearing surface away from thedisk when the disk is not rotating, and; a transducer located on thecarrier near the carrier trailing end for reading data from or writingdata to the disk.
 4. The transducer assembly according to claim 3wherein no portion of the air-bearing surface is located on the carrierdisk side between the carrier front end and the liquid-bearing skisurface.
 5. The transducer assembly according to claim 3 wherein thestruts are located on the air-bearing surface.
 6. The transducerassembly according to claim 3 wherein the struts are located outboard ofthe liquid-bearing ski surface, whereby no struts are located betweenthe ski surface and the disk front end.
 7. The transducer assemblyaccording to claim 3 wherein the air-bearing surface comprises twoair-bearing rails, each rail being spaced outboard of the liquid-bearingski surface.
 8. The transducer assembly according to claim 3 wherein theski surface on the carrier is the surface of a ski pad extending fromthe disk side of the carrier.
 9. The transducer assembly according toclaim 8 wherein the ski pad and the air-bearing surface are essentiallycoplanar.
 10. The transducer assembly according to claim 8 wherein theski pad has a leading edge having an essentially convex curvature. 11.The transducer assembly according to claim 8 wherein the sides of theski pad connecting the leading edge with the trailing edge define anangle which is greater than the maximum amount of skew of the carrierrelative to data tracks on the disk when the carrier is in the diskfile.
 12. The transducer assembly according to claim 3 furthercomprising means for connecting the carrier to the actuator of the diskfile, the carrier to actuator connecting means including means forbiasing the ski surface of the carrier into contact with the liquid filmon the disk.
 13. The transducer assembly according to claim 12 whereinthe carrier to actuator connecting means includes means for providinggenerally gimballed movement of the carrier, whereby the carrier maypitch and roll as its ski surface is forced into contact with thelubricant film during rotation of the disk.
 14. A transducer assemblyfor a data recording disk file which utilizes a liquid-bearing head-diskinterface, the assembly comprising:a transducer carrier having a diskside, a front end and a trailing end, the carrier comprising aliquid-bearing ski pad on the disk side near the trailing end and havinga convexly shaped leading edge wider than its trailing edge, a pair ofair-bearing rails on the disk side near the front end and outboard ofthe ski pad, and a plurality of struts to support the air-bearingsurface away from the disk when the disk is not rotating, and; atransducer located on the carrier near the carrier trailing end forreading data from or writing data to the disk.